Intermittent motion flying spot telecine

Abstract

An intermittent motion flying spot telecine capable of operating in real time provides an adequate film pull down time to allow the use of pin-registration by including a digital scan corrector (18) and a picture store and sequential-to-interlace converter (19) and by adjusting the CRT scanning circuitry (24). Three measures are employed: (I) the film is scanned with a sequential scanning raster and subsequent sequential-to-interlace conversion is performed, so as to combine two field blanking intervals into one longer one, (II) data is written into the picture store at a faster rate than required for the output and read out at a conventional rate, and (III) a triangular line scanning waveform is employed to allow line flyback time to be removed and the instantaneous line rate increased.

I claim: 
     
       1. An intermittent-motion flying spot telecine capable of operating in real time to scan cinematographic film to provide a video output signal at a video rate, the telecine comprising: a cathode ray tube having scanning means for producing a flying spot to scan the cinematographic film;   an optical system for imaging the spot onto the film to scan film frames of the film;   an intermittent film motion system for pulling the film through a film plane during times between scans of film frames;   light detector means for receiving the light passed by the film and producing an electrical signal response thereto at an output; and   means comprising a digital picture store coupled to the output of the light detector means;   the scanning means operating and the signal from the light detector means being written into the digitial picture store at a rate which is increased relative to the video rate, and the digital picture store providing the output video signal at the video rate, thereby increasing the times for pulling the film.   
     
     
       2. A telecine according to claim 1, including a sequential-to-interlace converter coupled to the output of the light detector means, and in which the scanning means operates with a sequential scanning raster. 
     
     
       3. A telecine according to claim 1, in which scanning means scans with a triangular of boustrophedral scan and at an instantaneous line rate increased relative to the line rate of the video output signal and including digital storage means coupled to the output of the light detecting means for reversing the samples of alternate lines of the signal and decreasing the line rate to provide the video output signal. 
     
     
       4. A telecine according to claim 2, in which the scanning means scans with a triangular or boustrophedral scan and at an instantaneous line rate increased relative to line rate of the video output signal and including digital storage means coupled to the output of the light detecting means for reversing the samples of alternate lines of the signal and decreasing the line rate to provide the video output signal. 
     
     
       5. Apparatus according to claim 1, including pin means for engaging the film being scanned to locate an image frame to be scanned at a predetermined position relative to the scan. 
     
     
       6. An intermittent-motion flying spot telecine capable of operating in real time to scan cinematographic film to provide a video output signal at a video rate, the telecine comprising: a cathode ray tube having scanning means for producing a flying spot to scan the cinematographic film;   an optical system for imaging the spot onto the film to scan film frames of the film;   an intermittent film motion system for pulling the film through a film plane during times between scans of film frames;   light detector means for receiving the light passed by the film and producing an electrical signal responsive thereto at an output, and   means comprising a sequential-to-interlace converter coupled to the output of the light detector means;   the scanning means operating with a sequential scanning raster to enable increased times for pulling the film.   
     
     
       7. A telecine according to claim 6, in which the scanning means scans with a triangular or boustrophedral scan and at an instantaneous line rate increased relative to the line rate of the video output signal and including digital storage means coupled to the output of the light detecting means for reversing the samples of alternate lines of the signal and decreasing the line rate to provide the video output signal. 
     
     
       8. Apparatus according to claim 6, including pin means for engaging the film being scanned to locate an image frame to be scanned at a predetermined position relative to the scan. 
     
     
       9. An intermittent-motion flying spot telecine capable of operating in real time to scan cinematographic film to provide a video output signal at a video rate, the telecine comprising: a cathode ray tube having scanning means for producing a flying spot to scan the cinematographic film;   an optical system for imaging the spot onto the film to scan film frames of the film;   an intermittent film motion system for pulling the film through a film plane during times between scans of film frames;   light detector means for receiving the light passed by the film and producing an electrical signal response thereto at an output; and   digital storage means coupled to the output of the light detecting means;   the scanning means scanning with a triangular or boustrophedral scan and at an instantaneous line rate increased relative to the video rate and the digital storage means being operative to reverse the samples of alternative lines of the output signal of the light detecting means and decrease the line rate to provide the video output signal at the video line rate, thereby increasing the times for pulling the film.   
     
     
       10. Apparatus according to claim 9, including pin means for engaging the film being scanned to locate an image frame to be scanned at a predetermined position relative to the scan.